1. Field of the Invention
The present invention relates to shovels and the structure of shovel heads. More specifically, the present invention relates to shovels where the heads of the shovels can be selectively moved relative the handle of the shovel.
2. Description of the Prior Art
Shovels come in many different shapes and styles. However, most every shovel has both a head and handle shaft that extends from the head. The shape of the shovel head and the handle shaft varies widely depending upon the intended use of the shovel. For example, snow shovels typically have large heads and short handles, which is ideal for shoveling snow. Digging shovels typically have spade shaped heads and long handles which is ideal for digging earth from the ground.
Regardless of the shape of the shovel, the manual act of shoveling remains basically the same. The head of the shovel is plunged into a material to be moved, such as snow, dirt, gravel, etc. An amount of material is then lifted up on the head of the shovel by manipulating the handle shaft. The person then turns and moves the head of the shovel to a discharging point wherein the shovel head is tilted and the material unloaded. The manual act of shoveling uses many different muscle groups in the arms, shoulders, backs and legs. The act of turning the shovel to the discharging point and twisting the shovel to unload the shovel head is particularly stressful to the back and arms of the person shoveling. As a result, people commonly strain muscles in their backs and arms when they do shovel.
Shovels typically have a straight handle shaft that is rigidly affixed to the head of the shovel. However, in the prior art, shovels have been developed where the head of the shovel can be selectively moved in relation to the position of the handle. Such prior art shovels are exemplified by U.S. Pat. No. 813,983 to Luney, entitled Snow Shovel; U.S. Pat. No. 2,221,219 to Nelson, entitled Adjustable Shovel; and U.S. Pat. No. 5,440,828 to Simpson, entitled Manual Snow Removal Tool. The primary use of such shovels is to angle the head of the shovel so that the shovel pushes material off to one side when the shovel is advanced along the ground like a plow. Although such prior art shovels have angled heads, the manual act of shovelling remains the same. Consequently, such prior art shovels do not alleviate the stresses to the muscles of the arms and back that are caused during the act of shoveling.
Although most shovels have straight handle shafts, some prior art shovels have contoured shafts that are configured to be more ergonomically efficient. By improving the ergonomics of the shovel handle shaft, the stresses experienced by the muscles in the arms and legs are decreased. Such prior art ergonomic shovel handle shafts are exemplified by U.S. Pat. No. 3,751,094 to Bohler, entitled Slidably Adjustable Auxiliary Lift Handle.
Although prior art shovels have been designed with shafts that better help a person grasp and manipulate the shovel, the prior art still has not addressed the problem of alleviating muscle stress caused by a persons' body twisting when shoveling. A need therefore exists in the art for a shovel that reduces the amount of twisting required in the act of shoveling, thereby reducing the number of injuries caused by twisting when shoveling. This need is met by the present invention as described and claimed below.